Bump google-spreadsheet version to fix encoding issues
version bump for npm
Added option to customize the extensions
(Need to output .json instead of .js)
Added option to use the default locale for missing translations
Added locales output to enable pipping to other tasks

Example:

```
task: {
  options: {
    languages: "<%= i18n_gspreadsheet.data.locales %>"
  }
}
```
Merge pull request #8 from LaurentGoderre/add-language-output

Added locales output to enable pipping to other tasks
Merge pull request #7 from LaurentGoderre/use-default-on-missing

Added option to use the default locale for missing translations
Merge pull request #6 from LaurentGoderre/add-ext-option

Added option to customize the extensions